President Trump came under fire this week for suggesting that Chicago, which has an off-the-charts murder rate, should implement stop, question, and frisk, a policy that helped drastically reduce New York City’s murder rate. This police tactic came into practice under former mayor Rudy Giuliani, then more widely under his successor Michael Bloomberg, but has been accused of being ineffective, unconstitutional, and racist.

None of these attacks are reasonable or fair, but what nobody can disagree with is that Giulani and Bloomberg’s methods made Gotham one of the safest big cities in America. Chicago, on the other hand, has remained a gangland in which murder is far too commonplace.

The city’s mayor, Rahm Emanuel, was not impressed by Trump’s suggestion. He said, “The failed policies he’s talking about have no place for a city that’s working together with communities about how to build — not only trust, but a collaborative and cooperative relationship.”

This is lovely to talk about, but the fact is that Chicago had 650 murders in 2017 while New York City had fewer than 300. Chicago has far fewer than half the population of New York. It makes all the sense in the world for the president to suggest that Chicago at least try a method of policing that coincided with dramatically reduced gun violence despite wrongheaded objections from liberal critics.

Yes, Stop, Question, and Frisk Worked

The ridiculous argument that stop, question, and frisk was irrelevant to the dramatic drop in gun crime in New York City is that when current Mayor Bill de Blasio ended it, the downward trend of gun violence continued. Well, of course it did. After decades of a policy that made criminals, especially gang members, wary of carrying illegal guns, it is only natural that they carry fewer illegal guns and thus commit fewer shootings.

It seems odd to speak about criminal culture, but gang members who make up a large part of shooting assailants and victims are a young cohort. They grew up in a New York City where carrying a gun could get them randomly locked up. Thus they are less likely to do so. When they do feel they need a gun, they go home, or to a communal gun-holding place to get it. That time cools things down and makes shootings less likely.

Yes, It’s Constitutional

We often hear that a federal judge found stop, question, and frisk unconstitutional. This is true. One judge in New York City did find this, although the controlling Supreme Court decision, Terry v. Ohio, finds the practice within constitutional bounds. So why hasn’t the Supreme Court weighed in to settle this? It’s because the de Blasio administration declined to appeal the decision.

This canard that the practice has been proven to be a civil rights violation is an absolute joke. All too often the liberal media presents this decision as somehow dispositive, when nothing could be farther from the case. Police absolutely have a right to stop and question a person they believe to be engaged in criminal activity. When they decide to frisk a person, they also have that right. That New York embraced this and Chicago didn’t goes a long way towards explaining why so many more young black men are shot to death in Chicago than in New York.

No, It’s Not Racist

In New York City in 2016, more than 80 percent of people arrested for murder were black or Hispanic. About 7 percent were white, and 4 percent were Asian. So the New York Police Department, not surprisingly, spends more time trying to check gun violence among blacks and Hispanics than they do among white or Asian people. This is not racism, it’s just identifying where the problem is and trying to address it.

The stop, question, and frisk policy is directly intended to stop the murders of minorities, since very few white people are murdered in New York. That is not racist, it’s practical, and it saves lives — mostly the lives of people of color. Chicago seems disinterested in this. Thus it appears this city’s liberal mayor would rather see black men die than challenge progressives’ ill-informed assumptions about proactive policing.

Bloomberg, who unlike Emanuel can point to a dramatic decrease in gun violence during his tenure, has become a Democrat and is looking at a 2020 presidential run. He told the New York Times this week in no uncertain terms that stop and frisk works. This will likely be a problem for his Democratic presidential nomination chances, but thankfully he isn’t throwing his own good work and that of the New York Police Department under the bus.

Giuliani and Bloomberg got results. Chicago’s corrupt Democratic political machine has not. Trump is right to call for employing in our new murder capital the methods that made Gotham the envy of the country regarding gun violence. And the lives he wants to save will mostly be lives of black and Hispanic men and boys.

The cynical opposition to this approach is wrongheaded and dangerous. Chicago needs stop, question, and frisk if it is ever to reach the level of safety and security we enjoy in New York City.

David Marcus is the Federalist's New York Correspondent and the Artistic Director of Blue Box World, a Brooklyn based theater project. Follow him on Twitter, @BlueBoxDave.